Hi,
is there an online resource available which lists running voltages and currents for various lamp types (hps, mh, mv)?
I usually use manufacturer's datasheets - PHILIPS or
OSRAM for European and GE for US
I ask because I make my ballasts and need to know the inductance/rectance.
This you have to calculate yourself. But for European types is much easier to buy factory-made chokes...
Currently I need some data for a 400W MH lamp, can the ballast itself be the same as for 400W MV? I know I need to use an ignitor but is the reactance similar? Running voltage would be helpful too.
If you are talking about EU Pulse Start MH 400W, on MV ballast would be underdriven and the MV ballast might overheat (as the lamp uses lower voltage drop then MV 400W, so there would be larger current then the ballast is designed for)
European MH are usually designed for EU's "SON" ballasts, so ~4A/~100V. But some are rated for 3.6A ballast as well (like OSRAM HQI-TS400W), then actual parameters of the lamp (input power, color temperature, CRI, lumen output) depend on actual ballast used (the above lamp 400W on SON 4A, 350W on 3.6A ballast,...)
US MH's are of two types: Pulse start and Probe start. Most pulse start are quite close to their EU's cousins, while Probe start types do not have their direct EU counterparts, as these generally require larger OCV then 230V for ignition, but the use of HV ignitors is not allowed.
Are the specs of european lamps (made for use with reactor ballast) the same or similar to other lamps made to run on a transformer-type ballast (with 120V line)?
No, European lamps use 130..150V for MV (when no voltage change over life is expected) and 70..100V for those, where increase of the voltage during life are generally expected (others), in order to keep the voltage below (or only slightly above) the half (130..140V) of expected mains (230V) voltage during whole life, to allow stable operation on a simple choke as ballast.
The US mains 120V would require max 70V on the lamp for simple choke ballast, but lamps with such low arc voltage would not be much efficient, so lamp spec's are not linked to the mains voltage anymore, as transformer type gear is expected, but are chosen for better expected efficacy instead.
But for both regions lamp spec's are standardized, so the same lamp family and wattage rating intended for given region is designed to operate with the same ballast.
In EU it is common to label ballasts/lamps with "nominal wattage" and lamp family code (MV80W, MH/SON70W), even if actual power input of a lamp is different (e.g. the MH lamp SLI "BriteLux TD 70W" consumes in reality 75W, but is intended for "70W" ballast).
In US the ANSI defined a code for each lamp spec, like H39, M59,... (I cannot put numbers, as i do not know them), but you might get these SPEC's when reading some more detailed lamp catalog (the GE one).
When making improvised lamps/ballasts combination, you should take into account, what the lamp voltage does during life and how the ballast will respond, mainly for saturated vapor types (esp. SON, CMH, some QMH; as increasing the input power, so temperature, lead to significant increase of filling pressure, so arc voltage, yielding possible overheat, so instability risk and cycling), in general the ballast should keep the lamp input watts in reasonable tolerance (for SON (0.8..1.4)*nominal watts, include mains tolerance) over all expected range of lamp's voltage
Any help is appreciated 
